Image pickup apparatus

ABSTRACT

An image pickup apparatus in which a pixel area including arrangement of a plurality of pixels each having a photoelectric conversion portion and a common output portion for sequentially amplifying and outputting signals from the plurality of pixels included in the pixel area are formed on a single semiconductor substrate, comprises a power supply unit for effecting power supply control of the common output portion independently of control on power supply to the pixel area, and a control circuit for effecting control to supply no power to the common output portion in a predetermined period after starting photo charge accumulation in the photoelectric conversion portion and supply the power to the common output portion before the end of a photo charge accumulation period in the photoelectric conversion portion.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an image pickup apparatus for pickingup an object image.

2. Related Background Art

As for this type of image pickup apparatuses in the past, there arethose already put on the market, such as an electronic camera with amemory card having a solid-state memory device as a recording medium forrecording and reproducing still images and moving images picked up bysolid-state image pickup elements such as CCD, CMOS and so on.

In general, this type of image pickup apparatus is comprised of a pixelportion, a read-out circuit portion and an output portion, and is placedon a single substrate (on-chip) for the sake of reducing noise.

As for the image pickup elements in the past, however, since theread-out circuit portion, output portion and pixel portion are on thesingle substrate, in the case where accumulation time becomes a longtime in minutes, heat is generated by the output portion and the like ofthe image pickup elements, which consume a lot of currents, and darkcurrents locally increase due to increase of thermal noise and a localtemperature rise in the pixels close to the output portion, therebyresulting in lower image quality.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an image pickup elementcapable of curbing increase of thermal noise and dark currents andpicking up a high-quality image.

To attain the object, an aspect of the present invention provides animage pickup apparatus in which a pixel area including arrangement of aplurality of pixels each having a photoelectric conversion portion and acommon output portion for sequentially amplifying and outputting signalsfrom the plurality of pixels included in the pixel area are formed on asingle semiconductor substrate, comprising: a power supply unit foreffecting power supply control of the common output portionindependently of control on power supply to the pixel area; and acontrol circuit for effecting control to supply no power to the commonoutput portion in a predetermined period after starting photo chargeaccumulation in the photoelectric conversion portion and supply power tothe common output portion before the end of a photo charge accumulationperiod in the photoelectric conversion portion.

Another aspect of the present invention provides the image pickupapparatus in which the pixel area including arrangement of a pluralityof pixels each having the photoelectric conversion portion and a commonoutput portion for sequentially amplifying and outputting signals fromthe plurality of pixels included in the above described pixel area areformed on a single semiconductor substrate, comprising: a power supplyunit for supplying a first power level and a second power level lowerthan the first power level to the common output portion; and a controlcircuit for effecting control to supply power of the second power levelto the common output portion in a predetermined period after startingphoto charge accumulation in the photoelectric conversion portion andsupply the first power level to the common output portion before the endof the photo charge accumulation period in the above describedphotoelectric conversion portion.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is comprised of FIGS. 1A and 1B showing block diagrams for aconfiguration of an electronic camera according to an embodiment of thepresent invention;

FIG. 2 is a flowchart showing a photographing operation procedure of animage processing apparatus 100;

FIG. 3 is a flowchart subsequent to FIG. 2 showing the photographingoperation procedure of the image processing apparatus 100;

FIG. 4 is a flowchart showing distance measurement and photometryprocedures in a step S114;

FIG. 5 is a flowchart showing a photographing procedure in a step S128;

FIG. 6 is a diagram showing an operation of an image pickup elementaccording to this embodiment;

FIG. 7 is a block diagram showing the image pickup element according tothis embodiment;

FIG. 8 is comprised of FIGS. 8A and 8B showing diagrams for details ofthe image pickup element according to this embodiment;

FIG. 9 is a diagram showing the operation of the image pickup element inFIGS. 8A and 8B;

FIG. 10 is a diagram showing one pixel constituting the image pickupelement in FIGS. 8A and 8B; and

FIG. 11 is a diagram for explaining noise of the image pickup element.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An image pickup element according to this embodiment will be describedby referring to the drawings. An image pickup apparatus according tothis embodiment will be applied to an electronic camera.

FIGS. 1A and 1B are block diagrams showing a configuration of theelectronic camera according to the embodiment. In FIGS. 1A and 1B,reference numeral 100 denotes an image processing apparatus. Referencenumeral 12 denotes a shutter having an iris function of controllinglight exposure of an image pickup element 14. Reference numeral 14denotes the image pickup element which converts an optical image into anelectrical signal.

Light incident on a photographing lens 310 in a lens unit 300 is guidedby a single lens reflex method through an iris 312, lens mounts 306 and106, a mirror 130 and a shutter 12 to form an optical image on the imagepickup element 14.

Reference numeral 16 denotes an A/D converter which converts an analogsignal outputted from the image pickup element 14 into a digital signal.Reference numeral 18 denotes a timing generation circuit for supplying aclock signal and a control signal to the image pickup element 14, A/Dconverter 16 and D/A converter 26, which is controlled by a memorycontrol circuit 22 and a system control circuit 50.

Reference numeral 20 denotes an image processing circuit which performspredetermined pixel interpolation and color conversion on data from theA/D converter 16 and data from the memory control circuit 22. The imageprocessing circuit 20 performs predetermined calculation by using imagedata picked up as required, and the system control circuit 50 performsan AF (auto focus) process, an AE (automatic exposure) process and an EF(electronics flash) process of a TTL (through the lens) method forcontrolling a shutter control unit 40 and a distance measurement controlunit 42 based on obtained calculation results. And the image processingcircuit 20 performs predetermined calculation by using the image datapicked up, and performs an AWB (auto white balance) process of the TTLmethod based on the obtained calculation results.

According to this embodiment, the distance measurement control unit 42and a photometry control unit 46 are provided for exclusive use.Therefore, it may have the configuration wherein the system controlcircuit 50 performs the AF (auto focus) process, AE (automatic exposure)process and EF (electronics flash) process by using the distancemeasurement control unit 42 and photometry control unit 46 instead ofperforming these processes by using the image processing circuit 20.

It may also have the configuration wherein the AF (auto focus), AE(automatic exposure) and EF (electronics flash) processes are performedby using the distance measurement control unit 42 and photometry controlunit 46, and these processes are further performed by using the imageprocessing circuit 20.

Reference numeral 22 denotes the memory control circuit which controlsthe A/D converter 16, timing generation circuit 18, image processingcircuit 20, image display memory 24, D/A converter 26, memory 30 andcompression and expansion circuit 32.

The data from the A/D converter 16 is written into the image displaymemory 24 or memory 30 via the image processing circuit 20 and memorycontrol circuit 22 or directly into the image display memory 24 or thememory 30 via the memory control circuit 22.

Reference numeral 24 denotes the image display memory and 26 denotes theD/A converter. Reference numeral 28 denotes an image display unitcomprising an LCD of the TFT method. The image data for display writtento the image display memory 24 is displayed on the image display unit 28via the D/A converter 26. In the case of displaying the picked-up imagedata one after another on the image display unit 28, it is possible toimplement an electronic finder function. The image display unit 28 canarbitrarily turn on and off the display according to an instruction ofthe system control circuit 50, so that it can significantly reduce powerconsumption of the image processing apparatus 100 in the case of turningoff the display.

Reference numeral 30 denotes the memory for storing still images andmoving images having been shot, and it has a sufficient storage capacityto store a predetermined number of the still images and the movingimages for a predetermined time. Therefore, it is also possible to writeimages into the memory 30 at high speed and by large amounts in thecases of continuously photographing of a plurality of still images or incase of panorama photographing. The memory 30 can also be used as a workarea for the system control circuit 50.

Reference numeral 32 denotes the compression and expansion circuit whichcompresses and expands the image data by adaptively-discrete cosinetransfer (ADCT) and so on, and it reads out the images stored in thememory 30 to compress or expand them and writes the processed data intothe memory 30.

Reference numeral 40 denotes the shutter control unit which controls theshutter 12 in collaboration with an iris control unit 340 forcontrolling the iris 312 based on photometric information from thephotometry control unit 46. Reference numeral 42 denotes the distancemeasurement control unit for performing the AF (auto focus) process, andit measures a focusing status of the image formed as the optical imageby guiding the light incident on the photographing lens 310 in the lensunit 300 by the single lens reflex method via the iris 312, lens mounts306 and 106, a mirror 130 and a sub-mirror for distance measurement (notshown).

Reference numeral 44 denotes a thermometer which detects an ambienttemperature in a photographing environment. In the case where thethermometer is in the image pickup element (sensor) 14, it is possibleto predict the dark currents of the sensor more accurately.

Reference numeral 46 denotes the photometry control unit for performingthe AE (automatic exposure) process, which measures an exposure statusof the image formed as the optical image by guiding the light incidenton the photographing lens 310 in the lens unit 300 by the single lensreflex method via the iris 312, lens mounts 306 and 106, a mirror 130and the sub-mirror for photometry (not shown). The photometry controlunit 46 also has an EF (electronics flash) process function bycollaborating with a flash 48. Reference numeral 48 denotes the flashwhich has a floodlighting function of AF fill light and an electronicsflash function.

As previously described, the system control circuit 50 can effectexposure control and AF (auto focus) control of a video TTL method overthe exposure (shutter) control unit 40, iris control unit 340 and adistance measurement control unit 342 on the basis of the resultscalculated by the image processing circuit 20 by using the image datapicked up by the image pickup element 14.

It is also possible to effect the AF (auto focus) control by using theresults of measurement by the distance measurement control unit 42 andthe results of calculation performed on the image data picked up by theimage pickup element 14 by the image processing circuit 20. Furthermore,it is also possible to effect the exposure control by using the resultsof measurement by the photometry control unit 46 and the results ofcalculation performed on the image data picked up by the image pickupelement 14 by the image processing circuit 20.

Reference numeral 50 denotes the system control circuit which controlsthe entire image processing apparatus 100, and it contains a well-knownCPU and so on. Reference numeral 52 denotes a memory which storesconstants, variables and programs for operation of the system controlcircuit 50. Reference numeral 54 denotes a display unit having a liquidcrystal display for displaying an operational state and a message bymeans of characters, images, voice and so on according to execution ofthe program on the system control circuit 50, a speaker and so on, whichis placed at one location or a plurality of locations easily visible andclose to an operating unit of the image processing apparatus 100. Thedisplay unit 54 is constituted by combining an LCD, an LED, apronunciation element and so on. Some functions of the display unit 54are provided inside an optical finder 104.

Of the display contents of the display unit 54, those to be displayed onthe LCD and so on include indications of single/continuousphotographing, a self-timer, a compression ratio, number of recordedpixels, number of recorded pictures, number of remaining possiblepictures, a shutter speed, an iris value, exposure correction, flash,red-eye reduction, macro photographing, buzzer setup, remaining clockbattery power, remaining battery power, error, information representedwith numbers of two or more digits, mounting statuses of recording media200 and 210, mounting status of a lens unit 300, communication I/Foperation, date and time, and a state of connection with an externalcomputer.

Of the display contents of the display unit 54, those to be displayed onthe optical finder 104 include the indications of focusing, completionof photographing preparations, shake alert, flash charging, completionof flash charging, shutter speed, iris value, exposure correction, andwriting operation to the recording medium.

Furthermore, of the display contents of the display unit 54, those to bedisplayed on the LED and so on include the focusing, completion ofphotographing preparations, shake alert, flash charging, completion offlash charging, writing operation to the recording medium, macrophotographing setup notification and secondary battery charging, forinstance.

Of the display contents of the display unit 54, those to be indicated bythe lamp and so on include a self-timer notification lamp, for instance.The self-timer notification lamp may be shared with the AF fill light.

Reference numeral 56 denotes an electrically erasable and recordablenonvolatile memory storing the programs and so on mentioned latertherein, where an EEPROM or the like is used as the nonvolatile memory.The nonvolatile memory 56 stores values such as various parameters andISO sensitivity, a setting mode and one-dimensional correction data usedwhen performing horizontal dark shading correction stored therein. Theone-dimensional correction data is created and stored when adjustment isperformed in a production process. As for the method of creating theone-dimensional correction data, there is a method such as performingprojective calculation on the image obtained by performing darkphotographing to obtain the data equivalent to one line.

As for the correction data, it may be the dark image picked up in theproduction process and stored as it is as two-dimensional data. However,some image pickup elements have a small vertical fixed pattern noise andthus require only correction in the horizontal direction.

Here, as for an important generation factor of the fixed pattern noise,there are differences (variations) in reading paths through which thesignals of the pixel portion reach a final output stage when reading thesignals from a circuit system of the image pickup element. FIG. 11 is adiagram showing mixture of the fixed pattern noise in horizontal andvertical directions. The horizontal fixed pattern noise depends on thedifference between the reading path of a vertical line a and the readingpath of a vertical line b in the drawing. The vertical fixed patternnoise depends on the difference between the reading path of a horizontalline c and the reading path of a horizontal line d in the drawing. Forinstance, in the case of the image pickup element wherein as shown inFIG. 11, the horizontal lines share the reading path and due tocontrivance of a circuit layout and so on, less noise is mixed whentransferring the signals of the horizontal lines to a common read-outcircuit, it is not necessary to correct the vertical fixed pattern noisebecause it is low. As for the image pickup apparatus using such an imagepickup element, it is possible to eliminate the fixed pattern noise bycorrecting the image by using horizontal one-dimensional correctiondata.

Reference numerals 60, 62, 64, 66, 68 and 70 denote the operating unitsfor inputting various operational instructions of the system controlcircuit 50, and they are comprised of a single combination or aplurality of combinations of switches, dials, touch panels, pointing byviewpoint detection, voice recognition and so on. Details of theoperating units will be described below.

Reference numeral 60 denotes a mode dial switch which can be set up byswitching among functional photographing modes such as an autophotographing mode, a program photographing mode, a shutter speedpreference photographing mode, an iris preference photographing mode, amanual photographing mode, a focal depth preference photographing mode,a portrait photographing mode, a landscape photographing mode, a closeupphotographing mode, a sport photographing mode, a night viewphotographing mode and a panorama photographing mode.

Reference numeral 62 denotes a shutter switch (SW1) which is turned onin the middle of the operation of a shutter button (not shown), and itinstructs a start of the operations such as the AF (auto focus) process,AE (automatic exposure) process, AWB (auto white balance) process and EF(electronics flash) process and so on.

Reference numeral 64 denotes a shutter switch (SW2) which is turned onat a time of completion of the operation of the shutter button (notshown). The shutter switch (SW2) 64 instructs a start of a series ofoperations, that is, an exposure process of writing the signal read fromthe image pickup element 12 as image data to the memory 30 via the A/Dconverter 16 and memory control circuit 22, a development process usingthe calculations in the image processing circuit 20 and memory controlcircuit 22, and a recording process of reading the image data from thememory 30, performing the compression on the compression and expansioncircuit 32 and writing the image data to the recording media 200 and210.

Reference numeral 66 denotes a reproduction switch which instructs astart of a reproduction operation of reading out the image photographedin a photographing mode from the memory 30 or the recording media 200and 210 and displaying it on the image display unit 28.

Reference numeral 68 denotes a single/continuous photographing switchcapable of setting a single mode in which it photographs one frame andthen is on standby on pressing the shutter switch SW2 and a continuousmode which performs photographing continuously while pressing theshutter switch SW2.

Reference numeral 69 denotes an ISO sensitivity setting switch which canset ISO sensitivity by changing a gain setting in the image pickupelement 14 or the image processing circuit 20.

Reference numeral 70 denotes the operating unit comprised of variousbuttons and touch panels, including a menu button, a set button, a macrobutton, a multi-screen reproduction page break button, a flash setupbutton, a single/continuous/self-timer switching button, a menumovement+ (plus) button, a menu movement− (minus) button, a reproducedimage movement+ (plus) button, a reproduced image− (minus) button, aphotographing image quality selection button, an exposure correctionbutton, a date/time setting button, a selection/switching button forsetting selection and switching of various functions on photographingand reproducing the panorama mode and so on, a determination/executionbutton for setting determination and execution of various functions onphotographing and reproducing the panorama mode and so on, an imagedisplay on/off switch for setting the image display unit 28 on or off, aquick review on/off switch for setting a quick review function forautomatically reproducing the shot image data immediately after thephotographing, a compression mode switch for selecting a compressionrate of JPEG compression or selecting a CCDRAW mode for digitizing thesignal of the image pickup element as-is and recording it on therecording medium, a reproduction switch capable of setting variousfunction modes such as a reproduction mode, a multi-screenreproduction/erasure mode and a PC connection mode, and an AF modesetting switch capable of setting a one shot AF mode in which an autofocus operation starts on pressing the shutter switch SW1 and a focusingstate is maintained once focus is attained and a servo AF mode in whichthe auto focus operation is continued while pressing the shutter switchSW1.

As for the functions of the plus button and minus button, it becomespossible to select numerical values and functions more lightly byproviding a rotary dial switch.

Reference numeral 72 denotes an electric power switch which can setswitching of power-on and power-off modes of the image processingapparatus 100. It can also set switching of power-on and power-off ofvarious auxiliary apparatuses such as the lens unit 300, an externalstrobe and the recording media 200 and 210.

Reference numeral 80 denotes an electric power control unit comprised ofa battery detection circuit, a DC to DC converter, a switch circuit forswitching a block to be energized and so on, and it detects whether ornot the battery is mounted, a type of the battery and remaining batterypower. It controls the DC to DC converter based on the detection resultsand instructions of the system control circuit 50 so as to supplynecessary voltage to the portions including the recording media for anecessary period of time.

Reference numerals 82 and 84 denote connectors, and 86 denotes anelectric power unit comprised of a primary battery such as an alkalicell or a lithium battery, a secondary battery such as an NiCd battery,an NiMH battery or an Li battery, an AC adapter and so on.

Reference numerals 90 and 94 denote interfaces to the recording mediasuch as a memory card and a hard disk, and 92 and 96 denote theconnectors for making connections to the recording media such as thememory card and hard disk. Reference numeral 98 denotes a recordingmedium attachment and detachment detection unit which detects whether ornot the recording media 200 and 210 are attached to the connectors 92and 96.

This embodiment has two systems of the interfaces and connectors forattaching the recording media provided thereto. However, a single systemor an arbitrary number of the systems of the interfaces and connectorsfor attaching the recording media may be provided thereto. As for theinterfaces and connectors of different standards, those compliant with aPCMCIA card, a CF (Compact Flash®) card and so on may be used.

Furthermore, in the case where it is constituted by using thosecompliant with a PCMCIA card, a CF (Compact Flash®) card and so on forthe interfaces 90 and 94 and the connectors 92 and 96, it is possible toconnect various communication cards such as a LAN card, a modem card, aUSB card, an IEEE 1394 card, a P1284 card, a SCSI card, and acommunication card of PHS and so on so as to mutually transfer the imagedata and management information attached to the image data between itand another computer and a peripheral such as a printer.

Reference numeral 104 denotes the optical finder which can guide thelight incident onto the photographing lens 310 via the iris 312, lensmounts 306 and 106, mirrors 130 and 132 in accordance with the singlelens reflex method so as to form an optical image and display it. Thus,it is possible to perform the photographing by using only the opticalfinder 104 without using an electronic finder function of the imagedisplay unit 28. The optical finder 104 has some of the functions of thedisplay unit 54, such as the indications of focusing, shake alert, flashcharging, shutter speed, iris value and exposure correction providedtherein.

Reference numeral 110 denotes a communication unit which has variouscommunication functions such as RS232C, USB, IEEE 1394, P1284, SCSI, amodem, LAN, radio communication and so on. Reference numeral 112 denotesthe connector for having the image processing apparatus 100 connected toanother apparatus by the communication unit 110 or an antenna in thecase of performing the radio communication.

Reference numeral 120 denotes the interface for connecting the imageprocessing apparatus 100 to the lens unit 300 in the lens mount 106.Reference numeral 122 denotes the connector for electrically connectingthe image processing apparatus 100 to the lens unit 300. Referencenumeral 124 denotes a lens attachment and detachment detection unitwhich detects whether or not the lens unit 300 is attached to the lensmount 106 or the connector 122.

The connector 122 conveys the control signal, status signal, data signaland so on between the image processing apparatus 100 and the lens unit300, and also has a function of supplying the currents of variousvoltages. The connector 122 may also be constituted to convey opticalcommunication, voice communication and so on in addition totelecommunication.

Reference numerals 130 and 132 denote the mirrors which guide the lightincident on the photographing lens 310 to the optical finder 104 inaccordance with the single lens reflex method. The mirror 132 may beconstituted either as a quick return mirror or as a half mirror.

Reference numeral 200 denotes the recording medium such as the memorycard or hard disk. The recording medium 200 has a recording unit 202comprised of a semiconductor memory, a magnetic disk and so on, aninterface 204 to the image processing apparatus 100, and a connector 206for making a connection to the image processing apparatus 100. Referencenumeral 210 denotes the recording medium such as the memory card or harddisk as with the recording medium 200. The recording medium 210 has arecording unit 212 comprised of the semiconductor memory, magnetic diskand so on, an interface 214 to the image processing apparatus 100, and aconnector 216 for making a connection to the image processing apparatus100.

Reference numeral 300 denotes the lens unit of an interchangeable lenstype. Reference numeral 306 denotes the lens mount which mechanicallylinks the lens unit 300 to the image processing apparatus 100. The lensmount 306 includes various functions of electrically connecting the lensunit 300 to the image processing apparatus 100 therein.

Reference numeral 310 denotes the photographing lens, and 312 denotesthe iris. Reference numeral 320 denotes the interface for connecting thelens unit 300 to the image processing apparatus 100 in the lens mount306. Reference numeral 322 denotes the connector for electricallyconnecting the lens unit 300 to the image processing apparatus 100.

The connector 322 conveys the control signal, status signal, data signaland so on between the image processing apparatus 100 and the lens unit300, and also has a function of having various currents supplied theretoor supplying the currents. The connector 322 may also be constituted toconvey an optical signal, an audio signal and so on in addition to theelectrical signal.

Reference numeral 340 denotes the iris control unit which controls theiris 312 in collaboration with the shutter control unit 40 forcontrolling the shutter 12 based on the photometric information from thephotometry control unit 46. Reference numeral 342 denotes the distancemeasurement control unit for controlling the focusing of thephotographing lens 310. Reference numeral 344 denotes a zoom controlunit for controlling zooming of the photographing lens 310. Referencenumeral 350 denotes a lens control circuit which controls the entirelens unit 300. The lens control circuit 350 also has the functions ofthe memory for storing the constants, variables and programs for theoperation and the nonvolatile memory for holding identity informationsuch as a number unique to the lens unit 300, management information,functional information such as an open iris value, a minimum iris valueand a focal length, current and past set values and so on.

The operation of the electronic camera having the above configurationwill be described. FIGS. 2, 3, 4 and 5 are flowcharts showing aphotographing operation procedure of the image processing apparatus 100.This processing program is stored in the storage medium such as thenonvolatile memory 56, and is loaded into the memory 52 to be executedby a CPU in the system control circuit 50.

At power-on such as a battery replacement, the system control circuit 50initializes flags, control variables and so on, and performspredetermined initialization necessary for each unit of the imageprocessing apparatus 100 (step S101). The system control circuit 50determines a setting position of the electric power switch 72 so as todetermine whether or not the electric power switch 72 is set atpower-off (step S102).

In the case where the electric power switch 72 is set at power-off, itperforms a predetermined termination process to change the display stateof each display unit to an ending state, record necessary parameters,set values and setup modes including the flags and control variables inthe nonvolatile memory 56 and shut down unnecessary power of each unitof the image processing apparatus 100 including the image display unit28 by means of the electric power control unit 80 (step S103), and thenreturns to the process in the step S102.

In the case where the electric power switch 72 is set at power-on, thesystem control circuit 50 determines whether or not there is a problemfor the operation of the image processing apparatus 100 as to aremaining capacity of the electric power unit 86 such as the battery orits operating status by means of the electric power control unit 80(step S104). If determined that there is a problem, it gives apredetermined warning to the display unit 54 by displaying the image oroutputting the voice (step S105), and returns to the process in the stepS102.

If determined that there is no problem as to the electric power unit 86,the system control circuit 50 determines the setting position of themode dial switch 60 so as to determine whether or not the mode dialswitch 60 is set in the photographing mode (step S106). In the casewhere the mode dial switch 60 is set in another mode, the system controlcircuit 50 performs a process according to the selected mode (stepS107), and then returns to the process in the step S102 thereafter.

In the case where the mode dial switch 60 is set in the photographingmode, it determines whether or not the recording media 200 and 210 aremounted, fetches the management information on the image data recordedon the recording media 200 and 210, and determines whether or not theoperational state of the recording media 200 and 210 is problematic tothe operation of the image processing apparatus 100, in particular, tothe operation of recording and reproducing the image data on therecording media (step S108). If determined that there is a problem, itgives a predetermined warning to the display unit 54 by displaying theimage or outputting the voice (step S105), and then returns to theprocess in the step S102.

If determined that there is no problem in the step S108, the systemcontrol circuit 50 checks a selection status of the single/continuousphotographing switch 68 for selecting single or continuous photographing(step S109). In the case where the single photographing is selected, asingle/continuous photographing flag is set at the single photographing(step S110). In the case where the continuous photographing is selected,the single/continuous photographing flag is set at the continuousphotographing (step S111). It is possible to set the single/continuousphotographing switch 68 by arbitrarily switching between the single modein which it photographs one frame and then is on standby on pressing theshutter switch SW2 and the continuous mode which performs continuouslyphotographing while pressing the shutter switch SW2. The state of thesingle/continuous photographing flag is stored in an internal memory ofthe system control circuit 50 or the memory 52.

The system control circuit 50 displays various setting statuses of theimage processing apparatus 100 with the images and voice by using thedisplay unit 54 (step S112). Here, it is also possible, in the casewhere an image display switch of the image display unit 28 is ON, todisplay various setting statuses of the image processing apparatus 100with the images and voice by using the image display unit 28.

It determines whether or not the shutter switch SW1 is depressed (stepS113), and returns to the process in the step S102 in the case where theshutter switch SW1 is not depressed. In the case where the shutterswitch SW1 is depressed, the system control circuit 50 performs adistance measurement/photometry process wherein the distance measurementprocess is performed to focus the photographing lens 310 on an objectand the photometry process is performed to determine the iris value andshutter speed (step S114). As for the photometry process, the flash isset up if necessary. Details of the distance measurement/photometryprocess will be described later.

And it determines whether or not the shutter switch SW2 is depressed(step S115), and in the case where the shutter switch SW2 is notdepressed, it determines whether or not the shutter switch SW1 is leftfree (step S116), and the processing in the step S115 and step S116 isrepeated until the shutter switch SW1 is left free or the shutter switchSW2 is depressed. In the case where the shutter switch SW1 is left freein the step S116, it moves on to the process in the step S102.

In the case where the shutter switch SW2 is depressed in the step S115,the system control circuit 50 determines whether or not there is animage-storing buffer space capable of storing the shot image data in thememory 30 (step S117). In the case where it determines that there is nospace capable of storing new image data in the image-storing bufferspace in the memory 30, it gives the predetermined warning to thedisplay unit 54 by displaying the image or outputting the voice (stepS118), and then returns to the process in the step S102.

For instance, the above includes the cases where it is immediately afterperforming the continuous photographing of the maximum shots storable inthe image-storing buffer space in the memory 30, so that the first imageto be read from the memory 30 and written to the recording media 200 and210 are not yet recorded on the recording media 200 and 210 and no freespace has been secured yet in the image-storing buffer in the memory 30.

In the case of compressing the shot image data and then storing it inthe image-storing buffer space in the memory 30, it is determined by theprocess in the step S117 whether or not there is the space capable ofstoring it on the image-storing buffer space in the memory 30considering that the image data amount after compression differsaccording to the setting of a compression mode.

In the case where it is determined in the step S117 that there is theimage-storing buffer space capable of storing the shot image data in thememory 30, the system control circuit 50 performs a photographingprocess wherein it reads out image pickup signals accumulated for apredetermined time in image pickup, from the image pickup element 14 andwrites the photographed image data into the predetermined space in thememory 30 via the A/D converter 16, the image processing circuit 20 andmemory control circuit 22 or directly from the A/D converter 16 via thememory control circuit 22 (step S119). Details of the photographingprocess will be described later.

When the photographing process in the step S119 is finished, the systemcontrol circuit 50 performs a WB (white balance) integral calculationprocess and an OB (optical black) integral calculation process requiredto read a part of the image data written to the predetermined space inthe memory 30 via the memory control circuit 22 and develop it so as tostore the calculation results in the internal memory of the systemcontrol circuit 50 or the memory 52.

And the system control circuit 50 reads out the photographed image datawritten to the predetermined space in the memory 30 by using the memorycontrol circuit 22 and the image processing circuit 20 if necessary, anduses the calculation results stored in the internal memory of the systemcontrol circuit 50 or the memory 52 to perform various developmentprocesses including the AWB (auto white balance) process, gammaconversion process and color conversion process (step S120).

In the development processes, a dark correction calculation process forcanceling dark current noise of the image pickup element 14 and so on isalso performed.

The system control circuit 50 reads out the image data written to thepredetermined space in the memory 30, performs an image compressionprocess according to the set mode on the compression and expansioncircuit 32, and writes the photographed image data undergone the seriesof processes into the free image space on the image-storing buffer spacein the memory 30 (step S121).

And the system control circuit 50 starts the recording process ofreading out the image data written to the image-storing buffer space inthe memory 30 and writing the read-out image data to the recording media200 and 210 such as the memory card and Compact Flash® card via theinterfaces 90 and 94 and the connectors 92 and 96 (step S122). Thisrecording process is performed on the image data each time thephotographed image data undergone the series of processes is writteninto the free image space on the image-storing buffer space in thememory 30.

While the image data is being written into the recording media 200 and210, a recording medium writing operation display such as blinking theLED is performed on the display unit 54 in order to indicate that it isin writing operation.

Furthermore, the system control circuit 50 determines whether or not theshutter switch SW1 is depressed (step S123). In the case where theshutter switch SW1 is left free, it returns to the process in the stepS102. In the case where the shutter switch SW1 is depressed, itdetermines the status of the single/continuous photographing flag storedin the internal memory of the system control circuit 50 or the memory 52(step S124). In the case where the single photographing is set, itreturns to the process in the step S123 and the current process isrepeated until the shutter switch SW1 is left free. In the case wherethe continuous photographing is set, it returns to the process in thestep S115 in order to photograph continuously and prepares for nextphotographing. Thus, the series of processes concerning thephotographing are finished.

FIG. 7 is a flowchart showing the distance measurement/photometryprocedure in the step S114. In the distance measurement/photometryprocess, exchange of various signals is performed between the systemcontrol circuit 50 and the iris control unit 340 or distance measurementcontrol unit 342 via the interface 120, connector 122, connector 322,interface 320 and lens control circuit 350.

The system control circuit 50 starts the AF (auto focus) process byusing the image pickup element 14, distance measurement control unit 42and distance measurement control unit 342 (step S201).

The system control circuit 50 guides into the distance measurementcontrol unit 42 the light incident on the photographing lens 310 via theiris 312, lens mounts 306 and 106, mirror 130 and sub-mirror fordistance measurement (not shown) so as to determine the focusing statusof the image formed as the optical image. And it performs the AF controlfor detecting the focusing status by using the distance measurementcontrol unit 42 while driving the photographing lens 310 by using thedistance measurement control unit 342 until it determines that thedistance measurement (AF) is focusing (step S202, S203).

If determined that the distance measurement (AF) is focusing in the stepS203, the system control circuit 50 determines a focusing distancemeasurement point of a plurality of distance measurement points in thephotographing screen, and stores the distance measurement data and/orsetting parameters together with the determined distance measurementpoint data in the internal memory of the system control circuit 50 orthe memory 52 (step S204).

Subsequently, the system control circuit 50 starts the AE (automaticexposure) process by using the photometry control unit 46 (step S205).The system control circuit 50 guides into the photometry control unit 46the light incident on the photographing lens 310 via the iris 312, lensmounts 306 and 106, mirrors 130 and 132 and photometric lens (not shown)so as to measure the exposure status of the image formed as the opticalimage. And it performs the photometry process by using the exposure(shutter) control unit 40 until it determines that the exposure (AE) isappropriate (step S206, S207).

If determined that the exposure (AE) is appropriate in the step S207,the system control circuit 50 stores the photometric data and/or settingparameters in the internal memory of the system control circuit 50 orthe memory 52 (step S207A).

The system control circuit 50 determines the iris value (Av value) andthe shutter speed (Tv value) according to the exposure (AE) resultdetected by the photometry process in the step S206 and thephotographing mode set up by the mode dial switch 60.

Here, according to the determined shutter speed (Tv value), the systemcontrol circuit 50 determines charge accumulation time of the imagepickup element 14, and performs the photographing process in the samedetermined charge accumulation time.

The system control circuit 50 determines whether or not the flash isnecessary according to the measurement data obtained by the photometryprocess in the step S206 (step S208). In the case where the flash isnecessary, it sets a flash flag and charges the flash 48 until chargingis completed (step S209, 210). And if the charging of the flash 48 iscompleted, it finishes this process and returns to the main process.

FIG. 5 is a flowchart showing a photographing procedure in the stepS119, FIG. 6 is a diagram showing the photographing operation at thistime, and FIG. 7 is a block diagram of the image pickup element.Hereafter, the photographing process will be described by using thedrawings. In this photographing process, the exchange of various signalsis performed between the system control circuit 50 and the iris controlunit 340 or distance measurement control unit 342 via the interface 120,connector 122, connector 322, interface 320 and lens control circuit350.

The system control circuit 50 moves the mirror 130 to a mirror-upposition by a mirror driving unit (not shown) (step S301), and drivesthe iris 312 up to a predetermined iris value by the iris control unit340 according to the photometric data stored in the internal memory ofthe system control circuit 50 or the memory 52 (step S302).

After performing charge clearing operation of the image pickup element14 (step S303), the system control circuit 50 starts charge accumulationof the image pickup element 14 (step S304), opens the shutter 12 by theshutter control unit 40 (step S305), and starts the exposure of theimage pickup element 14 (step S306).

And it determines whether or not the flash 48 is necessary according tothe flash flag (step S307), and flashes the flash 48 if necessary (stepS308).

The system control circuit 50 waits for the end of the exposure of theimage pickup element 14 according to the photometric data (step S309).When the exposure is finished, it closes the shutter 12 by the shuttercontrol unit 40 (step S310), and finishes the exposure of the imagepickup element 14.

The system control circuit 50 drives the iris 312 up to an open irisvalue by the iris control unit 340 (step S311), and moves the mirror 130to a mirror-down position by the mirror driving unit (not shown) (stepS312).

Next, it determines whether or not it has reached an on-time of theoutput portion of the image pickup element (step S313). In the casewhere it has reached a set time, the system control circuit 50 turns onthe power of the output portion of the image pickup element (step S314).Next, it determines whether or not the charge accumulation time haselapsed (step S315). In the case where the set charge accumulation timehas elapsed, the system control circuit 50 finishes the chargeaccumulation of the image pickup element 14 (step S316), and then readsout a charge signal from the image pickup element 14 so as to writesignal charges into the predetermined space in the memory 30 via the A/Dconverter 16, the image processing circuit 20 and memory control circuit22 or directly from the A/D converter 16 via the memory control circuit22 (step S317). On finishing the reading-out, it turns off the power ofthe output portion of the image pickup element (step S318).

Next, a description will be given by using FIGS. 6 and 7 as to theconfiguration of the image pickup element according to this embodiment,timing for accumulation and reading-out of photo charges, and power-onand power-off of the output portion in the final stage. Referencenumeral 14 denotes the image pickup element formed on a singlesemiconductor substrate by a CMOS process and so on. The image pickupelement has a pixel portion 501 in which a plurality of pixels having aphotoelectric conversion portion are arranged, a scanning circuit 502for outputting a timing pulse for reading the signals from the pixelportion, a common read-out circuit 503 for sequentially reading thesignals from the pixel portion, the output portion 504 for sequentiallyamplifying and outputting the signals from the read-out circuit, and apower supply switch 505 for switching between on and off of the powersupply to the output portion 504 formed thereon.

Here, a signal AMP_INH in FIG. 6 is the signal issued to the imagepickup element directly from the image processing apparatus 100, and thepower supply switch 505 is controlled by this signal. During theaccumulation, the power is supplied to the pixel portion 501, commonread-out circuit 503 and scanning circuit 502 in FIG. 7. The instant atwhich AMP_INH becomes high corresponds to the timing in the step S314 inFIG. 5, and the power supply switch 505 in the image pickup element isturned on.

Completion of read-out in FIG. 6 corresponds to the step S317 in FIG. 5.And the output portion off in FIG. 6 corresponds to the step S318 inFIG. 5.

If the series of processes are finished, it terminates this process andreturns to the main process.

As described above, the power supply switch for allowing the powersupply control over the output portion 504 is provided independently ofthe power supply control over the pixel portion 501 and so on, so thatthe above operation becomes possible.

Next, the configuration and operation of the image pickup element willbe described further in detail by using FIGS. 8A, 8B, 9 and 10.

FIGS. 8A and 8B are diagrams showing the configuration of the imagepickup element, FIG. 9 is a timing chart showing drive timing and outputsignals thereof, and FIG. 10 is a diagram showing one pixel of the imagepickup element in FIGS. 8A and 8B. Hereafter, a description will begiven by referring to FIGS. 8A, 8B and 9.

In FIGS. 8A and 8B, reference numeral 14 denotes the image pickupelement formed on a single semiconductor substrate by the CMOS processand so on. Reference numeral 601 denotes the pixel having color filtersin a Bayer arrangement, where the numbers in a parenthesis next to R(red), G (green) and B (blue) represent coordinates of the pixels. Here,the case of having the pixels arranged in 6×6 is shown in order tosimplify explanation. In reality, however, a considerable number ofpixels are arranged in a state of arrays.

As shown in FIG. 10, each pixel 601 includes a photoelectric conversionportion 701, an amplifying transistor 702 for amplifying and reading thesignals from the photoelectric conversion portion, a transfer transistor703 for transferring the signals of the photoelectric conversion portionto the amplifying transistor, a reset transistor 704 for resetting aninput portion of the amplifying transistor, and a selection transistor705 for reading the signals of a selected pixel.

The pixels 601 are connected to row reset lines R1 to R6, row transferlines T1 to T6 and row selection lines L1 to L6 in each rowrespectively. And the row reset lines R1 to R6 sequentially become High(hereafter, “H”) due to row reset signals supplied from a verticalscanning circuit 602 so that, by sequentially resetting thephotoelectric conversion portions in each row (φR1 to φR6), photo chargeaccumulation starts in each row. And the row transfer lines T1 to T6sequentially become H due to row transfer signals supplied from thevertical scanning circuit 602 so that, by sequentially transferring thecharges of the photoelectric conversion portions to the amplifyingtransistor in each row (φT1 to φT6), the photo charge accumulation issequentially terminated. Furthermore, the row selection lines L1 to L6sequentially become H due to row selection signals supplied from thevertical scanning circuit 602 so that the row to be read is selected.

The example shown in FIG. 9 represents the case where the row selectionsignal φL1 supplied to the row selection line L1 becomes H and the firstrow is selected (t3). Almost in the same timing for selecting a read-outrow and before reading the charges, signals φPTN1 and φPTN2 are renderedas H and MOS 621 and 622 are turned on so as to read noise components ofthe selected row to a capacity CTN. Next, signals φPTS1 and φPTS2 arerendered as H and MOS 623 and 624 are turned on (t4), and the photocharges accumulated in each pixel 1 of the selected row are superimposedon the noise components so as to be read to the capacity CTS. Thus, thenoise components of each pixel 1 and image signal componentssuperimposed on the noise components are stored in the capacities CTNand CTS respectively.

Next, the charges held by each of the capacities CTN and CTS aretransferred to differential amplifiers (output portions) 15 to 18 bycolumn selection signals supplied from first to fourth horizontalscanning circuits 611 to 614 comprised of shift registers and so on. Thedifferential amplifiers 15 to 18 outputs the image signal from whichnoise components are eliminated by subtracting the noise component fromthe image signal component superimposed on the noise components.

First, if the first and second horizontal scanning circuits 611 and 612render φH1 and φH2 as H, the corresponding MOS 625 to 628 are turned on,so that the charges read out from G (1, 1) and R (1, 2) to thecapacities CTN and CTS are transferred to the differential amplifiers615 and 616 via signal lines 101 and 102 respectively (t5). Thedifferential amplifier 615 eliminates the noise components from thephoto charges superimposed on the noise components, and outputs theimage signal (indicated by the same reference symbol as the pixel. G (1,1)) (OUT 1). Likewise, the differential amplifier 616 outputs the imagesignal R (1, 2) (OUT 2). Multiplexers 619 and 620 select thedifferential amplifiers 615 and 616 and output the image signals G(1, 1) and R (1, 2) respectively.

And in timing of t6, the third and fourth horizontal scanning circuits613 and 614 render φH3 and φH4 as H, and transfers the charges read fromG (1, 3) and R (1, 4) to the capacities CTN and CTS to the differentialamplifiers 617 and 618 via signal lines 623 and 624 respectively.

And the differential amplifier 617 eliminates the noise components fromthe photo charges superimposed on the noise components, and outputs theimage signal G (1, 3) (OUT 3). Likewise, the differential amplifier 618outputs the image signal R (1, 4) (OUT 4). The multiplexers 619 and 620select the differential amplifiers 617 and 618 this time and output theimage signals G (1, 3) and R (1, 4) respectively.

The above operation is repeated by one horizontal line so as to outputevery other G signal such as G (1, 1), G (1, 3) and G (1, 5) from anoutput terminal OUTA of the multiplexer 619 and every other R signalsuch as R (1, 2), R (1, 4) and R (1, 6) from an output terminal OUTB ofthe multiplexer 620.

Likewise, if φL2 is rendered as H by the vertical scanning circuit 602,a second row is selected and the above operation is repeated by one lineso as to output every other B signal such as B (2, 1), B (2, 3) and B(2, 5) from the output terminal OUTA of the multiplexer 19 and everyother G signal such as G (2, 2), G (2, 4) and G (2, 6) from the outputterminal OUTB of the multiplexer 20.

Here, as for the image pickup element in FIGS. 8A and 8B, it ispossible, with the power supply switch 505, to control the power supplyto the differential amplifiers 615 to 618 independently of the pixelportion 501, common read-out circuit 503, vertical scanning circuit 602and first to fourth horizontal scanning circuits 611 to 614.

In the configurations and operations in FIGS. 8A, 8B and 9, the photocharge accumulation is sequentially terminated row by row, and readingis sequentially started row by row.

For that reason, the power supply switch 505 is turned on in order tosupply the power to the differential amplifiers 615 to 618 predeterminedtime earlier (between t3 and t4) than terminating the photo chargeaccumulation of the pixels in the first row.

Though it is not shown, the power supply switch 505 is turned off afteroutputting the charges of the pixels in the final row from thedifferential amplifiers 617 to 618, so that the power is not supplied tothe differential amplifiers 617 to 618.

As described above, the power supply switch 505 is turned on in order tosupply the power to the differential amplifiers 615 to 618 predeterminedtime earlier (between t3 and t4) than terminating the photo chargesaccumulation of the pixels in the first row. Therefore, the differentialamplifiers are in a stable state when the signals read from the pixelsare inputted thereto. For that reason, there is no need to read out thesignals from the pixels after the differential amplifiers become stableso that the processing time can be reduced. In particular, it iseffective in the cases of the continuous photographing and movingpictures wherein the images are continuously outputted from the imagepickup element.

The above described the embodiment of the present invention. However,the present invention is not limited to this embodiment.

For instance, the power source of the output portion (differentialamplifiers) of the image pickup element is turned on and off accordingto the embodiment. It is also possible, however, to turn on and off thecommon read-out circuit simultaneously with the output portion.

According to this embodiment, the power source of the output portion ofthe image pickup element is turned on at the predetermined timeimmediately before terminating the photo charge accumulation. It is alsopossible, however, to turn on the power source of the output portionafter terminating the accumulation and then start the read-out. In thiscase, it is also possible to start the read-out after waitingstabilization time of the circuit at power-on of the output portion.Furthermore, it may have the configuration wherein the power source ofthe output portion is turned on only during the accumulation. In thiscase, however, the processing time becomes a little longer.

Furthermore, the power supply switch according to this embodiment iscontrolled by the signal from the outside, that is, the configurationwherein the timing of on and off can be changed by the signal from theoutside (configuration capable of variable control). Therefore, it isalso possible to perform variable control over the timing for turning onthe output portion.

Furthermore, the power source of the output portion is turned on and offaccording to this embodiment. However, almost the same effect can beobtained by providing a “low current consumption” mode instead ofpower-off and switching between “on and low current consumption.”

To be more precise, the power is supplied to the pixel portion, commonread-out circuit and scanning circuits from one terminal (firstterminal) and to an output amplifier from another terminal (secondterminal) to be able to supply the power to the image pickup elementfrom the two terminals. And the system control circuit 50 exerts controlto supply a first power level and a second power level lower than thefirst power level to the second terminal.

Furthermore, the above embodiment showed the case of switching betweenthe single photographing and continuous photographing by using thesingle/continuous photographing switch 68. It is also possible, however,to switch between the single photographing and continuous photographingaccording to selection of an operating mode with the mode dial switch60.

Furthermore, it is possible, as for the photo charge accumulation in thepixel portion, to provide a long-time mode having long accumulation timeand a short-time mode having short accumulation time so as to switch thepower source of the output portion in the long-time mode and not toswitch it in the short-time mode. To be more specific, it may have theconfiguration wherein the power is continuously supplied during thephoto charge accumulation time.

The above embodiment discloses the case of performing the photographingoperation by moving the mirror 130 between the mirror-up position andmirror-down position. It is also possible, however, to constitute themirror 130 as the half mirror and perform the photographing operationwithout moving the mirror.

Furthermore, the recording media 200 and 210 may be constituted not onlyby the memory card such as the PCMCIA card or Compact Flash®, hard diskand so on but also by an optical disk such as a micro DAT, amagnet-optical disk, a CD-R or a CD-RW, or a phase-change optical disksuch as a DVD. Furthermore, the recording media 200 and 210 may be acomposite medium having the memory card and hard disk as a unit. In thiscase, it may have the configuration wherein a part of the compositemedium is detachable.

According to this embodiment, the recording media 200 and 210 areseparate from the image processing apparatus 100, and are arbitrarilyconnectable. It is also possible, however, to have one or all of therecording media fixed to the image processing apparatus 100. It may alsohave the configuration wherein an arbitrary number, that is, one pieceor a plurality of pieces of the recording media 200 and 210 areconnectable to the image processing apparatus 100.

According to this embodiment, the program codes shown in the flowchartsin FIGS. 2 to 5 are stored in an ROM which is the recording medium. Asfor the recording medium for supplying the program codes, it is notlimited to the ROM, but a flexible disk, a hard disk, a nonvolatilememory card and so on may be used.

As described above, according to this embodiment, it is possible, in theimage pickup element having the pixel portion and read-out circuitportion on the same substrate, to turn off the power source of theoutput portion during the accumulation period so as to preventtemperature rise in the image pickup element and prevent degradation ofimage quality due to increase in thermal noise and dark currents. It isalso possible, by rendering the timing for exerting control changeablefrom the outside, to provide the image pickup element of excellenttemperature characteristics capable of easily changing the timing forturning on and off the power source according to length of theaccumulation time and ambient temperature. Furthermore, the image pickupelement contains the circuit for controlling the power source therein sothat the control signals and power supply lines are saved to allowminiaturization of the circuits.

Many widely different embodiments of the present invention may beconstructed without departing from the spirit and scope of the presentinvention. It should be understood that the present invention is notlimited to the specific embodiments described in the specification,except as defined in the appended claims.

1-8. (canceled)
 9. An image sensor control apparatus which controls animage sensor in which a pixel area and a common output portion areformed, wherein the pixel area is configured to include a plurality ofpixels, each having a photoelectric conversion portion, and the commonoutput portion is configured to amplify and output signals of theplurality of pixels included in the pixel area, said apparatuscomprising: a power supply unit configured to control power supply tothe common output portion independently of controlling the power supplyto the plurality of pixels; and a control circuit configured to switchover power supply control of the power supply unit, wherein if a firstmode is set, the power supply unit stops power supply to the commonoutput portion for a predetermined period, and wherein if a second modeis set, the power supply unit continues to supply the power to thecommon output portion during the photo-charge accumulation period,wherein a photo-charge accumulation period of the photoelectricconversion portion in the first mode is longer than a photo-chargeaccumulation period in the second mode.
 10. The image pickup apparatusaccording to claim 9, wherein said control circuit variably controls theperiod during which the power supply to the common output portion isstopped.
 11. The image pickup apparatus according to claim 9, whereinsaid power supply unit is formed on a single semiconductor substrate.12. The image pickup apparatus according to claim 9, wherein the powersupply unit continues to supply the power to the common output portionduring the photo-charge accumulation period without switching the powersupply thereto.
 13. An image sensor control apparatus which control aimage sensor in which a pixel area and a common output portion areformed, wherein the pixel area is configured to include a plurality ofpixels, each having a photoelectric conversion portion, and the commonoutput portion is configured to amplify and output signals of theplurality of pixels included in the pixel area, said apparatuscomprising: a power supply unit configured to control power supply tothe common output portion independently of controlling the power supplyto the plurality of pixels; and a control circuit configured to switchover power supply control of the power supply unit, wherein if a firstlength of a photo-charge accumulation period is set, the power supplyunit stops power supply to the common output portion for a predeterminedperiod, and wherein if a second length of a photo-charge accumulationperiod is set, the power supply unit continues to supply the power tothe common output portion during the photo-charge accumulation period,wherein the first length of a photo-charge accumulation period is longerthan the second length of a photo-charge accumulation period.
 14. Theimage pickup apparatus according to claim 13, wherein said controlcircuit variably controls the period during which the power supply tothe common output portion is stopped.
 15. The image pickup apparatusaccording to claim 13, wherein said power supply unit is formed on asingle semiconductor substrate.
 16. The image pickup apparatus accordingto claim 13, wherein the power supply unit continues to supply the powerto the common output portion during the photo-charge accumulation periodwithout switching the power supply thereto.